Machines | Mechanical Advantage Using a Rope and Pulleys for Vehicle Recovery 9:1
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I try to explain how to get a mechanical advantage of 5:1 and 9:1 by arranging a rope and pulleys. I pull a truck that is stuck in Florida sugar sand out by hand. I also show how to tie a bowline knot.
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Sorry I don't understand what the friction hitch is or how it is tied to both ropes. Can you explain by diagram or give me a website that explains how it works. Or can you do another video showing the friction hitch knot in detail on where and how you tied it. Thanks. Doug
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This procedure is taught in military vehicle recovery and rigging training because it works.
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I ride a bike solo deep in the backwoods and have been stuck several times. I carry a 3-1 setup and can now go as far as a 6-1. It has saved my ass several times and is light and packs in my backpack.
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awesome bro thanks a lot
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My question has to do with the ratings of the pulleys involved. If I am trying to move an 8000 lb object and using the method described here, what is the required rating for the pulleys? 4 ton (or bigger), each pulley at 1 ton?
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Pretty good explanation, and kudos to you for the caveat of the the ratio between number of pulleys and distance of pull
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thank you, Great Video!, 👍
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Sheet bend knot is also one of the easiest knots to untie after a hard pull.
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thanks for uploading
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Caution, the rope you choose should NOT be a dynamic climbing rope as it is not designed for heavy static loads and the load ratings can be more difficult to understand as you are using it for something its not made to do. If you are going to practice this method (which is not bad at all) make sure to use the right gear or you can put your self into danger.
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well i don't get it if you have five lines it a 5:1 regardless of if yo hook to the load?
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I am certain that everyone has a couple of hundred feet of rope laying around and a slew of pulleys. I have a 4X4 and do not have that problem.
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Why do they call it the Bowline? They should call it the Rabbit Tree Hole Knot since most of us aren't sailors securing the bow (front pointy part) of our ships.
A Figure-8 knot and Alpine Butterfly will also work. If you put a load on them by doing a tractor pull event it'll take a hammer banging on any of the three knots to untie them. You wimped out here making it look like the bowline is easy to untie by not substantially loading with a dynamic pull from an F-550 making a running start of a few feet before cinching the knot.
Using naval terminology again..., If you don't have a tree and are stuck in the mud the Pull-Pal Winch Ground Anchor is a cool device to have in your toolbox to use with your 5:1 block & tackle setup. It kind of looks like a farmer's plow. The harder you pull on it the deeper it digs in. -
Umm, a 9:1 pulling on a 5:1 is a 45:1 not a 14:1. Unless I missed something in your explanation.
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Best explanation and real life application of mechanical advantage with pulleys. Great job.
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Anther great anchor point that you always can use is bury your spare tier. With a rope attached of coarse.
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Thank you - excellent presentation and clear explanation.
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For those kind of trucks that have the hitch on the bumper, do yourself a favor and attach the rope underneath the bumper, straight to the chassis - around the bumper, lead in on top, lead out on bottom. I bent more than one bumper thinking that the hitch is a point of strength - it ain't. Fucking hate this bumper design.
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Excellent presentation.... thank you. I must admit that I had to google how to tie a friction hitch knot.... once again thank you.
Ray